The couple will attend an orchid naming ceremony at the Singapore Botanic Gardens where, in a poignant moment, they will look at the flower that Diana herself never got to see.

William’s late mother was meant to visit the bloom but she was killed in a car crash, exactly 15 years ago tomorrow, before she could make the trip.

The Duchess of Cambridge will also make her first speech abroad and her second speech ever during the Diamond Jubilee tour, where she and William will represent the Queen in Singapore, Malaysia, the Solomon Islands and Tuvalu from September 11 to 19.

Kate will address staff and patients of a Kuala Lumpur hospice where she will say a few words about her experiences of working with her own charity East Anglia’s Children’s Hospices in the UK.

She and William will also sit at the bedsides of desperately ill children during their visit to the hospice on arrival in Malaysia on September 13.

The jam-packed tour will also see them visit the Borneo rainforests - the oldest in the world - where they will scale a rope bridge and hopefully meet the endangered Borneo orangutan.

When they arrive in Tuvalu on September 18 they will be carried off their plane in a traditional island welcome mirroring the welcome the Queen and Philip received when they were carried off their boat in 1982.

Private Secretary Jamie Lowther-Pinkerton admitted yesterday he wasn’t exactly sure how the arrival was going to work, adding: “It remains to be seen whether it’s a canoe or some kind of platform...I think they will be carried off in something, it will be great.”

The couple will travel with an entourage of eight; Two private secretaries, two press officers, adviser Sir David Manning, a PA, an orderly to organise the entourage, and a hairdresser, paid for privately, for Kate.

Kate will choose all her own outfits for the tour, and the couple will wear traditional dress for certain events, such as the state dinner in Tuvalu.